Feng chiralN,N′-dioxide ligands: uniqueness and impacts

Organic Chemistry Frontiers, Год журнала: 2023, Номер 10(14), С. 3676 - 3683

Опубликована: Янв. 1, 2023

Privileged Feng ligands feature designer N , ’-dioxide amides with a unique conformational and coordination flexibility. This highlight summarizes the increasingly profound impact of on modern catalytic asymmetric synthesis.

Язык: Английский

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Asymmetric Cross-Coupling of Aldehydes with Diverse Carbonyl or Iminyl Compounds by Photoredox-Mediated Cobalt Catalysis

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(15), С. 10857 - 10867

Опубликована: Апрель 8, 2024

The asymmetric cross-coupling of unsaturated bonds, hampered by their comparable polarity and reactivity, as well the scarcity efficient catalytic systems capable diastereo- enantiocontrol, presents a significant hurdle in organic synthesis. In this study, we introduce highly adaptable photochemical cobalt catalysis framework that facilitates chemo- stereoselective reductive cross-couplings between common aldehydes with broad array carbonyl iminyl compounds, including N-acylhydrazones, aryl ketones, aldehydes, α-keto esters. Our methodology hinges on synergistic mechanism driven photoredox-induced single-electron reduction subsequent radical–radical coupling, all precisely guided chiral catalyst. Various optically enriched β-amino alcohols unsymmetrical 1,2-diol derivatives (80 examples) have been synthesized good yields (up to 90% yield) high stereoselectivities >20:1 dr, 99% ee). Of particular note, approach accomplishes unattainable transformations disparate partners without reliance any external photosensitizer, thereby further emphasizing its versatility cost-efficiency.

Язык: Английский

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Desymmetrization–Addition Reaction of Cyclopropenes to Imines via Synergistic Photoredox and Cobalt Catalysis

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(28), С. 18892 - 18898

Опубликована: Июль 5, 2024

Herein, we designed a reaction for the desymmetrization-addition of cyclopropenes to imines by leveraging synergy between photoredox and asymmetric cobalt catalysis. This protocol facilitated synthesis series chiral functionalized cyclopropanes with high yield, enantioselectivity, diastereoselectivity (44 examples, up 93% yield >99% ee). A possible mechanism involving cyclopropene desymmetrization Co-H species imine addition Co-alkyl was proposed. study provides novel route important extends frontier metallaphotoredox

Язык: Английский

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A Remarkable Influence of La(III)/N,N′-Dioxide Structure on Asymmetric Formal Substitution of 3-Bromo-3-substituted Oxindoles with TMSCN

ACS Catalysis, Год журнала: 2024, Номер 14(5), С. 2908 - 2916

Опубликована: Фев. 10, 2024

The structural elucidation of chiral rare-earth-based catalysts in asymmetric reactions holds significant importance as it is crucial for comprehending their operational mechanisms and broadening applications the realm synthesis. Herein, a LaIII/(L3-RaMe3)2 complex was identified to be more active enantioselective than LaIII/L3-RaMe3 formal substitution racemic 3-bromo-3-substituted oxindoles with TMSCN. experimental studies theoretical calculations disclosed that partial dissociation N,N′-dioxide ligand involved catalytic process LaIII/(L3-RaMe3)2. These insights provided rationale remarkable effect catalyst structures on results nonlinear observed current reaction system. This protocol offers straightforward efficient pathway synthesize various 3-cyano-3-substituted (53 examples, up 99% yield, 98% ee). In addition, synthesis bioactive compound CRTH2 receptor antagonist obvious inhibitory several products viability cancer cells demonstrate potential utility this methodology.

Язык: Английский

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Catalytic Asymmetric Dearomative [2 + 2] Photocycloaddition/Ring-Expansion Sequence of Indoles with Diversified Alkenes

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(33), С. 23457 - 23466

Опубликована: Июль 12, 2024

Developing novel strategies for catalytic asymmetric dearomatization (CADA) reactions is highly valuable. Visible light-mediated photocatalysis demonstrated to be a powerful tool activate aromatic compounds further synthetic transformations. Herein, dearomative [2 + 2] photocycloaddition/ring-expansion sequence of indoles with simple alkenes was reported, providing facile access enantioenriched cyclopenta[

Язык: Английский

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Advancing Heterogeneous Organic Synthesis With Coordination Chemistry‐Empowered Single‐Atom Catalysts

Advanced Materials, Год журнала: 2024, Номер unknown

Опубликована: Сен. 18, 2024

Abstract For traditional metal complexes, intricate chemistry is required to acquire appropriate ligands for controlling the electron and steric hindrance of active centers. Comparatively, preparation single‐atom catalysts much easier with more straightforward effective accesses arrangement control The presence coordination atoms or neighboring functional on supports' surface ensures stability single‐atoms their interactions individual substantially regulate performance Therefore, collaborative interaction between surrounding environment enhances initiation reaction substrates formation transformation crucial intermediate compounds, which imparts significant catalytic efficacy, rendering them a valuable framework investigating correlation structure activity, as well mechanism in organic reactions. Herein, comprehensive overviews both homogeneous complexes reactions are provided. Additionally, reflective conjectures about advancement synthesis also proposed present reference later development.

Язык: Английский

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NiH-Catalyzed Regio- and Enantioselective Hydroalkylation for the Synthesis of β- or γ-Branched Chiral Aromatic N-Heterocycles

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(40), С. 22122 - 22134

Опубликована: Сен. 25, 2023

A nickel hydride-catalyzed regio- and enantioselective hydroalkylation reaction was developed to give access a library of chiral β- or γ-branched aromatic N-heterocycles. This intriguing asymmetric transformation features excellent selectivities, step- atom-economies, generating two kinds products through one synthetic strategy. Furthermore, the possible mechanism extensively investigated using numerous control experiments density functional theory calculations.

Язык: Английский

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Enantioselective anti-Dihalogenation of Electron-Deficient Olefin: A Triplet Halo-Radical Pylon Intermediate

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(8), С. 4808 - 4818

Опубликована: Фев. 16, 2023

The textbook alkene halogenation reaction establishes straightforward access to vicinal dihaloalkanes. However, a robust catalytic method for dihalogenizing electron-deficient olefins in an enantioselective manner is still under development, and its mechanism remains controversial. Herein, we disclose efficient regio-, anti-diastereo-, dibromination, bromochlorination, dichlorination reactions of enones catalyzed by chiral N,N'-dioxide/Yb(OTf)3 complex. With the combination electrophilic halogen halide salts as halogenating agents, array homo- heterodihalogenated derivatives achieved moderate good enantioselectivities. Moreover, DFT calculations reveal that novel triplet halo-radical pylon intermediate probable accounting exclusive regio- anti-diastereoselectivity.

Язык: Английский

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Quinone-Initiated Photocatalytic Enantioselective Giese Radical Addition with Ethers, Thioethers, Amines, and Alkanes

ACS Catalysis, Год журнала: 2024, Номер 14(16), С. 12031 - 12041

Опубликована: Июль 29, 2024

Photocatalytic enantioselective Giese radical addition with inert C(sp3)–H bonds represents a highly efficient and economically favorable approach to synthesizing diverse value-added chiral molecules from abundant feedstock. Herein, we disclose quinone-initiated photocatalytic asymmetric of α-substituted acrylamides by applying simple quinones as HAT photocatalysts in combination N,N′-dioxide/praseodymium(III) catalyst. A wide array ethers, thioethers, selenide, amines, alkanes can smoothly transform into the corresponding α-aryl amide derivatives satisfactory enantioselectivities (68 examples, up 95% ee) under mild conditions. Based on spectroscopy studies control experiments, catalytic cycle was proposed, DFT calculations revealed that interaction between quinone Lewis acid essential for enantio-induction back hydrogen atom transfer process.

Язык: Английский

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Recent Advances in Visible Light‐induced Asymmetric Transformations of Carbonyl Compounds into Chiral Alcohols

ChemCatChem, Год журнала: 2023, Номер 15(21)

Опубликована: Авг. 16, 2023

Abstract Visible light‐induced photocatalysis has been widely investigated, which offers exciting opportunities to build new catalytic platforms that are unattainable under ground state conditions. Asymmetric a longstanding challenge due the high reactivity of photogenerated intermediates leading strong background reaction. Carbonyl group is an important fundamental scaffold in organic synthesis. The photocatalytic asymmetric transformations carbonyl compounds for synthesizing enantioenriched secondary and tertiary alcohols significant value but remain problematic. Even so, series intriguing works concerning this topic have reported recent year. This review summarizes advances area, mainly dividing into single synergetic catalyst systems, mechanism each reaction discussed.

Язык: Английский

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